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    <script>
        function isLeapYear(year) {
            return year % 4 === 0 && year % 100 !==0 || year % 400 === 0;
        }
        function getFebDayCount (year) {
            if (isLeapYear(year)) {
                return 29;
            }
            return 28;
        }

        console.log(getFebDayCount(2004));
    </script>
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